title: Broad epigenetic signature of maternal care in the brain of adult rats.
abstract: BACKGROUND
  Maternal care is associated with long-term effects on behavior and epigenetic programming of the NR3C1 (GLUCOCORTICOID RECEPTOR) gene in the hippocampus of both rats and humans. In the rat, these effects are reversed by cross-fostering, demonstrating that they are defined by epigenetic rather than genetic processes. However, epigenetic changes at a single gene promoter are unlikely to account for the range of outcomes and the persistent change in expression of hundreds of additional genes in adult rats in response to differences in maternal care.
  
  
  RESULTS
  We examine here using high-density oligonucleotide array the state of DNA methylation, histone acetylation and gene expression in a 7 million base pair region of chromosome 18 containing the NR3C1 gene in the hippocampus of adult rats. Natural variations in maternal care are associated with coordinate epigenetic changes spanning over a hundred kilobase pairs. The adult offspring of high compared to low maternal care mothers show epigenetic changes in promoters, exons, and gene ends associated with higher transcriptional activity across many genes within the locus examined. Other genes in this region remain unchanged, indicating a clustered yet specific and patterned response. Interestingly, the chromosomal region containing the protocadherin-α, -β, and -γ (Pcdh) gene families implicated in synaptogenesis show the highest differential response to maternal care.
  
  
  CONCLUSIONS
  The results suggest for the first time that the epigenetic response to maternal care is coordinated in clusters across broad genomic areas. The data indicate that the epigenetic response to maternal care involves not only single candidate gene promoters but includes transcriptional and intragenic sequences, as well as those residing distantly from transcription start sites. These epigenetic and transcriptional profiles constitute the first tiling microarray data set exploring the relationship between epigenetic modifications and RNA expression in both protein coding and non-coding regions across a chromosomal locus in the mammalian brain.
authors.affiliation: Douglas Mental Health University Institute, Montreal, Quebec, Canada. patrick.mcgowan@utoronto.ca
authors.forename: Patrick O
authors.initials: PO
authors.lastname: McGowan
authors.forename: Matthew
authors.initials: M
authors.lastname: Suderman
authors.forename: Aya
authors.initials: A
authors.lastname: Sasaki
authors.forename: Tony C T
authors.initials: TC
authors.lastname: Huang
authors.forename: Michael
authors.initials: M
authors.lastname: Hallett
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Meaney
authors.forename: Moshe
authors.initials: M
authors.lastname: Szyf
mesh_terms: D000367:Age Factors; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D001921:Brain / Q000378:metabolism*; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D005260:Female; D020869:Gene Expression Profiling; D056426:Genetic Loci; D006657:Histones / Q000378:metabolism; D008297:Male; D008425:Maternal Behavior / Q000502:physiology*; D046228:Microarray Analysis; D051381:Rats; D020318:Rats, Long-Evans; D011965:Receptors, Glucocorticoid / Q000235:genetics; D050436:Regulatory Elements, Transcriptional / Q000235:genetics; D054928:Validation Studies as Topic
chemical_list: D006657:Histones; C542344:NR3C1 protein, rat; D011965:Receptors, Glucocorticoid